Merge tag 'kvm-x86-hyperv-6.8' of https://github.com/kvm-x86/linux into HEAD

KVM x86 Hyper-V changes for 6.8:

 - Guard KVM-on-HyperV's range-based TLB flush hooks with an #ifdef on
   CONFIG_HYPERV as a minor optimization, and to self-document the code.

 - Add CONFIG_KVM_HYPERV to allow disabling KVM support for HyperV "emulation"
   at build time.

2 files changed, 26 insertions, 1 deletions

diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
index 26b628d84594..f482216bbdb8 100644
--- a/arch/x86/include/asm/kvm-x86-ops.h
+++ b/arch/x86/include/asm/kvm-x86-ops.h
@@ -55,8 +55,10 @@ KVM_X86_OP(set_rflags)
 KVM_X86_OP(get_if_flag)
 KVM_X86_OP(flush_tlb_all)
 KVM_X86_OP(flush_tlb_current)
+#if IS_ENABLED(CONFIG_HYPERV)
 KVM_X86_OP_OPTIONAL(flush_remote_tlbs)
 KVM_X86_OP_OPTIONAL(flush_remote_tlbs_range)
+#endif
 KVM_X86_OP(flush_tlb_gva)
 KVM_X86_OP(flush_tlb_guest)
 KVM_X86_OP(vcpu_pre_run)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index a565a2e70f30..b093c2191cd3 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -937,8 +937,10 @@ struct kvm_vcpu_arch {
 	/* used for guest single stepping over the given code position */
 	unsigned long singlestep_rip;
 
+#ifdef CONFIG_KVM_HYPERV
 	bool hyperv_enabled;
 	struct kvm_vcpu_hv *hyperv;
+#endif
 #ifdef CONFIG_KVM_XEN
 	struct kvm_vcpu_xen xen;
 #endif
@@ -1095,6 +1097,7 @@ enum hv_tsc_page_status {
 	HV_TSC_PAGE_BROKEN,
 };
 
+#ifdef CONFIG_KVM_HYPERV
 /* Hyper-V emulation context */
 struct kvm_hv {
 	struct mutex hv_lock;
@@ -1125,9 +1128,9 @@ struct kvm_hv {
 	 */
 	unsigned int synic_auto_eoi_used;
 
-	struct hv_partition_assist_pg *hv_pa_pg;
 	struct kvm_hv_syndbg hv_syndbg;
 };
+#endif
 
 struct msr_bitmap_range {
 	u32 flags;
@@ -1136,6 +1139,7 @@ struct msr_bitmap_range {
 	unsigned long *bitmap;
 };
 
+#ifdef CONFIG_KVM_XEN
 /* Xen emulation context */
 struct kvm_xen {
 	struct mutex xen_lock;
@@ -1147,6 +1151,7 @@ struct kvm_xen {
 	struct idr evtchn_ports;
 	unsigned long poll_mask[BITS_TO_LONGS(KVM_MAX_VCPUS)];
 };
+#endif
 
 enum kvm_irqchip_mode {
 	KVM_IRQCHIP_NONE,
@@ -1348,8 +1353,13 @@ struct kvm_arch {
 	/* reads protected by irq_srcu, writes by irq_lock */
 	struct hlist_head mask_notifier_list;
 
+#ifdef CONFIG_KVM_HYPERV
 	struct kvm_hv hyperv;
+#endif
+
+#ifdef CONFIG_KVM_XEN
 	struct kvm_xen xen;
+#endif
 
 	bool backwards_tsc_observed;
 	bool boot_vcpu_runs_old_kvmclock;
@@ -1442,6 +1452,7 @@ struct kvm_arch {
 #if IS_ENABLED(CONFIG_HYPERV)
 	hpa_t	hv_root_tdp;
 	spinlock_t hv_root_tdp_lock;
+	struct hv_partition_assist_pg *hv_pa_pg;
 #endif
 	/*
 	 * VM-scope maximum vCPU ID. Used to determine the size of structures
@@ -1614,9 +1625,11 @@ struct kvm_x86_ops {
 
 	void (*flush_tlb_all)(struct kvm_vcpu *vcpu);
 	void (*flush_tlb_current)(struct kvm_vcpu *vcpu);
+#if IS_ENABLED(CONFIG_HYPERV)
 	int  (*flush_remote_tlbs)(struct kvm *kvm);
 	int  (*flush_remote_tlbs_range)(struct kvm *kvm, gfn_t gfn,
 					gfn_t nr_pages);
+#endif
 
 	/*
 	 * Flush any TLB entries associated with the given GVA.
@@ -1825,6 +1838,7 @@ static inline struct kvm *kvm_arch_alloc_vm(void)
 #define __KVM_HAVE_ARCH_VM_FREE
 void kvm_arch_free_vm(struct kvm *kvm);
 
+#if IS_ENABLED(CONFIG_HYPERV)
 #define __KVM_HAVE_ARCH_FLUSH_REMOTE_TLBS
 static inline int kvm_arch_flush_remote_tlbs(struct kvm *kvm)
 {
@@ -1836,6 +1850,15 @@ static inline int kvm_arch_flush_remote_tlbs(struct kvm *kvm)
 }
 
 #define __KVM_HAVE_ARCH_FLUSH_REMOTE_TLBS_RANGE
+static inline int kvm_arch_flush_remote_tlbs_range(struct kvm *kvm, gfn_t gfn,
+						   u64 nr_pages)
+{
+	if (!kvm_x86_ops.flush_remote_tlbs_range)
+		return -EOPNOTSUPP;
+
+	return static_call(kvm_x86_flush_remote_tlbs_range)(kvm, gfn, nr_pages);
+}
+#endif /* CONFIG_HYPERV */
 
 #define kvm_arch_pmi_in_guest(vcpu) \
 	((vcpu) && (vcpu)->arch.handling_intr_from_guest)